What printing resolution do I need?

What is DPI and how does it relate to print size?

DPI stands for dots-per-inch. Any digital printer in the world converts your images to dots and places those dots on the paper/media. These small colored dots merge up to form your printed image. A lot of complicated algorithms go into how to printer optimizes its internal printing mechanism but we’ll keep it extremely easy to understand.

You would surely know that your images on your computer are also made of up several dots – called pixels. So when we say an image is 1240 by 900 – we’re essentially saying there are 1240 columns and 900 rows of pixels – a total of 1240 x 900 = 1,116,000 dots (or pixels) that make up the image.

Now when we go ahead and print this image, the printer needs to understand how large we want to print it. So we tell the printer that this image is 100 dpi (or ppi). Which means we are asking the printer to place 100 dots of this image per inch. And since we have 1240 dots in the horizontal direction, the width of the print will be 12.4 inches. Similarly, the height will be 9 inches.

Remember the number of pixels is the information contained in an image. You can’t change it. (You can do so forcefully, but it really doesn’t help – see later questions). So if an image is 1240 x 900 pixels, we can choose a resolution for the image (in a software like Photoshop) to suit our printing requirements. The smaller the resolution, the larger the print we can get from the same image. But if we keep the resolution too low (or print size too high) then the print gets pixellated and doesn’t look good. This is where experience comes in. We have been printing images for years now and these are just some rough guidelines to follow for the best resolutions.

Very important: You DO NOT need 300 dpi for all printing formats. Especially not for large-format printing (where the sizes in the range of a few feet)

Sunboard / Vinyl printing: Due to the relatively smooth surface, a good printing resolution is around 100-120 dpi. You can of course use a larger resolution at your print size, but it won’t make a difference.

Flex printing: Since the flex surface is extremely rough, anything around 72-80 dpi is good enough. But for very very large sizes like hoardings – we even use resolutions between 35-60 dpi sometimes.

Paper printing: Coming to small format printing the widely accepted norm is 300 dpi. The reason is that we have to hold paper prints very close to our eyes. So the printing has to be extremely crisp which means resolution must be high.

What does hi-res mean?

Hi-res simply stands for high-resolution. There is no standard for this and it is relative. Basically any image that fits your print size and resolution is hi-res. Anything that is way below that is low-res.

Can I convert low-res files to hi-res?

There can be no automatic way of conversion. Only because if a file does not contain enough information to display it in a very large size, you can’t force it to acquire more info. If a file is 1200 x 900 pixels, you can force it to resize to 2400 x 1800 pixels in many software but they use approximation algorithms to extend already available data.

If you have a file 1200 x 900 which you forcefully resize to 2400 x 1800, and you print it in 100 dpi resolution (24 inches x 18 inches), you will see the the result will not be very satisfactory. The pixels will appear botched and squared. Only because the files does not have enough information to be represented in such a size. You can get away with this if the print has to be seen from a large distance – that’s when a relatively low distance works.

Usually, if you have a really large print size say more than 10ft, it will probably be viewed for a greater distance and that is when you can afford to have a low-resolution print without the viewer noticing.

Where do I find hi-res files?

Images and pictures with very good resolution and print size capability are found all across in the internet. Depending on your use, you can purchase images from stock sites such as shutterstock.com, istockphoto.com, 123rf.com etc. You can also find large sized images on google and bing image searches but be careful about copyright issues.

Finally, if get prints at Amitoje India, we will guide you through the process and make sure the files that you give are good enough to be printed at the size you want.

5 Ways to print and brand your store’s window and glass

The store glass is the first thing that makes an impression to the visitor. Therefore, you should try to be as innovative and clear in your message for the window as you can. There are a lot of unique options to brand your glass. We describe a few common ways to brand your glass and the materials used in the process. Feel free use them in isolation or combination for your own store.

1. Vinyl cut letters: Custom cut self-adhesive vinyl into the shape of letters, logos and messages is an extensively used technique that allows you to deliver your message without obstructing the view inside the store. We have all used these to make sale announcements, advertise new entries and seasons changes. However, it is dull and overused.

Vinyl cut letters on Window glass

Vinyl cut design on glass

2. Semi-transparent graphics: Digital prints on translucent vinyls can be conveniently pasted on glass. They can also be cut outs as per your creative. The major benefit here is that you can install a large creative, maybe cover the glass top to bottom and also allow the customers to look what’s going on inside , behind the glass. It doesn’t make the glass seem like a solid wall but an entry into a new dimension of great products.

Translucent vinyl printing on glass

3. Opaque creatives: While translucent prints are great, it is possible, that they might not make as much impact as a solid opaque print would. The drawback here is that you must keep the size small so that your glass still allows inside activity to be seen. This kind of effect is achieved by printing on opaque self-adhesive vinyl (with our without a cut out) and applying it directly onto the window.

Opaque vinyl print on glass

Opaque vinyl printing on glass

4. Frosted vinyl: Frosted/Etching self-adhesive vinyl was invented to give clear glass a frosted look. Frosting is a physical process done on glass that makes selected portions rough and opaque. This film provides the same effect quite well. The frosted film can be cut into any shape and can be used to represent your brand logo or your upcoming campaign. Further, this vinyl can be printed and it gives a really unique output in terms of aesthetics.

Frosted vinyl pasted on glass

5. One way vision: The one-way-vision/mesh printed vinyl has a mesh-like structure. The speciality of this material is that from the outside it looks like a solid print (maybe around 75% opacity) but from the inside of the store everything outside is visible. This is a good option if you want to print huge creatives and cover the whole glass. If your store is inside a mall or has a good amount of lighting inside, the opacity from outside further reduces (approximately around 50%).

One way vision film

Now that you are aware of the basic techniques to brand your glass, ask your design team to play around with these ideas and make something unique to accurately portray your brand and it’s ideology.